<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .nbv{
            width:300px;
            height:300px;
            background-color: rgb(235, 240, 240);
            border-radius: 150px;
            margin: auto;
            box-shadow: 10px 10px 20px 10px black inset;
        }
        .nav{
            height: 41px;
            border-top:3px solid #ff8500;
            border-bottom:1px solid #edeef0;
            background-color: #fcfcfc;
            line-height: 41px;
            width: 1000px;
            margin:auto;
        }
        .nav a{
            display: inline-block;
            font-size:22px;
            color:black;
            text-decoration: none;
            padding: 0 20px;
        }
        .nav a:hover{
            background-color: aqua;
        }
        
    </style>
</head>
<body>
    <div class="nbv"></div>
    <div class="nav" align="center">
        <a href="#">新浪微博</a>
        <a href="#">中文网</a>
        <a href="#">移动客户端</a>
        <a href="#">微博</a>
    </div>
    
</body>
</html>